An optical information processor deals very easily with two dimensional data. However, the electro-optical coupling in a real time basis becomes hard, because of the necessity of using transparency variations, such as photographic films, as input data.
This paper presents a new method of transforming electric signals into a two dimensional optical transparency variations, on a real time. The process consists of some ultrasonic vibrators placed in a tank filled with water that control in each instant the locations of the ultrasonic waves traveling through the water. Using the Schlieren method, only the light diffracted by the ultrasonic waves can be obtained. So, the presence or absence of these waves will be transformed into transparency variations.
As an application, a reference pattern was generated with a pattern recognition device. When the reference character matches with the unknown one, the light caught by a photomultiplier will be maximum (Optical Pattern Matching Method). As a first trial, figures from “0” to “9” were used to be recognized; though it is still in an initial step, it was possible to classify each figure. By other hand, using a K.D.P. light modulator as an optical shutter, the possibility to apply this device as a characted printer was confirmed. The character “E” was generated and its picture was taken.